Power-driven dispenser assembly



United States Patent ABSTRACT: An automatic dispenser for coiled steel strapping materials, or the like, havin dispensing tray which is intermittently powerelectric motor, or other suitable mean trolling switch and a movable device constructed and arran ble material-dispensing tray to control the motor in re to demand for strapping material.

[54] POWER-DRIVEN DISPENSER ASSEMBLY 4 Claims, 6 Drawing Figs.

[51] Int.

[50] Field ofSearch..i................ ..............i........

Patented Dec. 1, 1970 3,544,029

Sheet 1 of2' W-zz' Pr y /L"ZZ&Q%J/JIELGW Pa tented Dec. 1, 1970 v 3,544,029

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POWER-DRIVEN DISPENSER ASSEMBLY This invention relates generally to a mechanism for dispensing steel strapping for use in conjunction with manual or pneumatically operated tools of the type utilized to tension and secure strapping materials around cartons, or bundles. One example of this type of tool is disclosed in U.S. Pat. No. 3,198,218, granted on Aug. 3, 1965, to A. l. Ericsson et al., and assigned to the assignee of the present invention. More particularly, this invention relates to a strapping material dispensing assembly in which the strapping material may be easily fed from a rotatably mounted coil by means of powerdriven rotation of the material-supporting tray and a movable sensor unit and power control means is utilized to start and stop the drive in response to a demand for strapping material from the strapping tool, or strapping tool operator.

In the past, it has been common practice to mount or'support a coil of strapping material on a rotatable tray, or reellike structure, and to turn the reel either manually, or by power, in order to feed the material therefrom. One example of this type of structure is found in US. Pat. No. 3,061,235, granted to H. C. Lingle on Oct. 30, 1962, and assigned to the assignee of the present invention. Prior dispensing devices have been adequate for the purpose for which they have been designed, but certain operational deficiencies have been more recently encountered as the increasing demand of feeding rates has occurred due to the development of more proficient strapping tools. With the greater demand for higher feeding rates, there has been the necessity to provide larger amounts of coiled strapping material to be handled by the dispenser to eliminate the need for periodic replenishing of the supply of coiled material. Because of the increase in size of the coils of strapping material, there has been an increase in the weight of the material, which has affected the ability to start and stop the rotation of the supporting tray. It has become increasingly difficult to accelerate or decelerate the rotating coil of strapping material and the material-supporting tray, and as a result, the coil can overtravel due to rotational inertia and a slack or untensioned length of strapping material is released from the coil and becomes uncontrollable. This condition can result in snarls in the strapping material, which can permanently kink the material and upset the operation of the strapping tool, as well as cause losses to material and operating time devoted to untangling the material.

Steel strapping material of the type utilized with this invention is often quite resilient and is usually wound in coils having a radius of curvatures substantially less than that of the so called coil set, or bundle curve (residual curve). As a result, whenever steel strapping material gets out of control from the the wound coil, it will spring out in the fashion of what might be expected from a clock spring and the uncontrolled convolutions will kink, snarl, and entangle.

Furthermore, with the growth in size of power-operated strapping material dispensers, there has been a need to conveniently control the normal direction of the material as it is fed out, or payed out" from the dispensing tray. These dispensing trays and the coils of material supported thereon have become very heavy, and it is not convenient to change the position of the dispenser so as to change the direction of the material as required due to a change in position of the strapping tool, or strapping tool operator. Accordingly, there is a present need for a machine which will provide an arrangement to selectively set the normal direction of "payouts" of the strapping material in relation to the position of the operator without requiring the operator to physically alter the position of the complete dispensing assembly.

The present invention has solved the foregoing problems by providing a mechanism for dispensing steel strapping material automatically upon demand from the operator by providing an inexpensive and effective movable sensor and control unit which will start and stop the power drive, as well as handle any slack or untensioned strapping material which may result from changes in the demand of material received from the strapping tool, or strapping tool operator. When strapping material is no longer demanded, or required by the tool, the present invention will shut off the power and insure the return of any loose material to the wound coil of strapping material. The machine will be thus prepared for the next operation without any slack or entangled material, which would prevent efficient use. Additional means have been provided in the present invention to allow adjustment of the direction of the feeding of the strapping material from the dispensing tray in at least four general positions. By this means, there is an elimination of the requirement for shifting the entire dispensing assembly and strapping material coil to alter the direction of feeding of the material as it is required do due to changes in position of the strapping tool.

Other advantages of the present invention will become apparent from the following description of the preferred em bodiment thereof taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a top plan view of the dispenser assembly with parts broken away and removed to illustrate the power drive arrangement and the movable sensor and drive controlling mm;

FIG 1A is an electrical circuit schematic drawing showing the electrical interconnection between the electric motor, the manual electric switch, and the motor control electric switch;

FIG. 2 is a side elevational cross-sectional view of the dispenser assembly taken along line 2-2 of FIG. 1;

FIG. 3 is a fragmentary view of the movable sensor unit taken along line 3-3 of FIG. 1;

FIG. 4 is a fragmentary sectional view taken along the line 4-4 ofFlG. l; and

FIG. 5 is a fragmentary sectional view taken along the line 5-5 of FIG. 1.

The apparatus of the present invention provides a positive means for retarding the movement of the rotating coil of strapping material after the length of material has been withdrawn from the coil and satisfied the demand of the strapping too] operator, thus eliminating any undesirable overtravel of the coil of strapping material and reaching a condition in which loose and uncontrolled convolutions of strapping material would spring outwardly and become snarled, or entangled. The present invention operates in response to a tug, or a tensioning of the strapping material by the strapping tool operator, which will pull on a movable sensor unit, actuating the power drive motor controlling switch and causing rotation of the dispenser. This relatively small amount of effort on the part of the strapping tool operator is all that is required to control this relatively heavy power-driven unit. As soon as the demand for material has been satisfied, a small amount of slack will be encountered in the material being fed from the dispensing tray, and this slack will cause the movable sensor unit to move outwardly, opening the power drive switch and stopping the motor means and drive. Not only does the movable sensor unit effectively and simply start and stop the power drive, but it also restores any loose or slack winds of the material to the coil.

The dispenser assembly frame includes a base member 10 and a pair of outwardly projecting stabilizer members 12 secured thereto by any conventional means, such as welding. The members 10 and 12 are arranged to rest on the ground, floor, or any suitable level surface to provide a structure to support and stabilize the remainder of the dispensing assembly.

At one end of the base member 10, there is located a manually operated electrical switch 14, a swingably mounted electric motor 16, a power takeoff drive 18, including a conventional worm and wheel gear structure (not shown) and a power output friction drive wheel 20. p

The swingably mounted electric motor 16 is coupled to the base member 10 by means of a vertically disposed shaft 22 secured to the underside of the electric motor 16 and positioned in an upstanding bearing structure 24, which is secured to the base member 10, as by welding, or other conventional means. This support arrangement can be of any suitable structure and does not form a part of the present invention.

As previously mentioned, a power takeoff drive of a conventional worm and wheel structure is coupled to the output shaft of the electric motor 16 and includes a vertically disposed output shaft 26 secured to the gear drive at its upper end and secured to friction wheel 20 at its opposite end. The friction wheel 20 is in continuous engagement with the outer periphery of an annular dispenser tray 28. which is supported on the base 10, as will be hereinafter discussed.

In order to secure continuous engagement of the friction wheel 20 with the outer periphery of the annular dispenser tray 28, an upstanding L-shaped support 30 is secured by any suitable means to base member and provides a support for a compression spring arrangement 32, which is positioned between the support member 30 and the outer housing of the power takeoff drive 18. By this means, the motor 16 can pivot on shaft 22 within the bearing 24 under the influence of compression spring 32 and continuously force friction wheel against the outer periphery of annular tray 28.

Referring particularly to FIG. 2, it will be seen that an upstanding spindle 34 is secured to an intermediate portion of the bass base member 10, as by welding, or the like. Spindle or shaft 34 provides a stationary support for the rotation of annular tray 28. Annular dispensing tray 28 comprises an upwardly directed flange portion 36, which provides the outer periphery of the tray 28, a bottom portion 38, a central hub portion 40 welded thereto, and a bearing member 42 pressed into the hub portion 40 to provide anantifriction bearing arrangement for efficient rotation of the tray 28 around upstanding shaft or spindle 34. To further enhance the rotational efficiency of the annular tray 28, a thrust bearing 44 is positioned between the lower end of bearing 42 and the upper surface of member 10. The bearing 42 and 44 are made of any conventional material and do not form part of the present invention.

Detachably secured to the upper end of spindle or shaft 34 is an annular supporting disc 46 which is utilized to support the electrical motor control switch 48 and a movable sensor unit 50. The structure and connection of the electrical switch 48 and movable sensor unit 50 will be discussed hereinafter.

It will be noted that the spindle or shaft 34 is provided with an internal bore 52, an upper end portion 54, and a pair of threaded holes 55.

Referring particularly to FIGS. 4 and 5, it will be seen that annular supporting disc 46 is detachably connected to the upper end 54 of spindle 34 by means of a pair of conventional bolts 56 which pass through apertures 58 in disc 46 and are threaded into bolt holes 60 of the spindle 34. There are four apertures 58 in supporting disc 46 which are equally spaced radially from the center of disc 46 and are alined with threaded apertures 60 of the spindle 34. By selectively alining a pair of apertures 58, it is possible to position the disc 46 in four positions 90 apart for purposes which will be hereinafter explained.

An electrical cord 62 is coupled between the motor 16, the manual electrical switch 14, and the motor control electrical switch 48. This cord 62 is secured to the underside of base member 10 and passes upwardly through the internal bore 52 of the spindle 34 and, an as seen in FIG. 1, is connected by suitable means to switch 4-8, in order to connect the power supply, the motor and the various switching devices for automatic control of the dispenser assembly.

The switch 48 is provided with an outwardly extending resilient lever or contact member 64 which responds to rotational movement of sensor unit 50. When resilient lever 64 is moved in one direction, motor control switch 48 will be closed to start the motor 16 and when it is moved in the opposite direction, switch 48 is opened to shut off the electrical power to motor 16 and stop the movement of tray 28.

It will be noted in FIGS. 1 and 2 that electrical switch 48 is mounted on support disc 46 by means of a housing or cover plate 66 which is secured thereto by bolts 68. Switch 48 is secured to the internal surface of housing 66 by screws 70.

Positioned adjacent the outer periphery of annular disc 46 is the movable sensor unit 50 which comprises an angularly depending sensor arm and guide tube 72, a C-shaped bracket 74 welded to the upper end of guide tube 72, and a pivotal support 76 comprising a bolt 78 and bearing means 80, which pivotal support connects bracket 74 to the outer periphery of annular disc 46.

Connected to the upper bight of bracket 74 is a depending pin or contact member 82 which is arranged radially from pivotal support 76 and switch lever 64 to engage or contact member 64 as movable sensor unit 50 responds during the dispensing operation.

As will be seen, coil C is positioned on the inside of tray 28 and engages outer periphery 36 and bottom portion 38 and the internal wind is slid through tube 72 of the movable sensor unit 50 and projects from the upper end thereof and extends outwardly from where it is connected to the strapping tool (not shown).

In operation, as the strapping material C is utilized by the strapping tool (not shown), the operator and/or the strapping tool will tug and tension the outwardly extending length of the strapping material. As tension is applied to the inner wind of the strapping material C, the arm 72 will be caused to swing inwardly towards the central axis and spindle 34 of the dispenser assembly. As the arm 72 swings inwardly against the resilient biasing of the strapping material C, pin or contact member E2 will swing about pivotal support 76 and engage outwardly extending lever or contact member 64 of the switch 48.

When pin 82 of the sensor unit 50 engages lever 64 of the switch 48 and moves the lever sufficiently, the switch 48 will be closed and electrical power will be transmitted to the motor 16. The motor 16 will be actuated and rotational power will be transmitted to worm and gear power takeoff mechanism 18 to the friction wheel 20. The friction wheel 20 will turn the outer periphery of the annular dispensing tray 28 until a sufficient length of strapping material is provided to the operator to satisfy the demand. As soon as the demand has been satisfied, a certain slack, or the tautness will be relaxed in the outwardly extending length of the strapping material C and the residual curvature of the strapping material will cause the arm 72 to swing outwardly toward the innermost wind of the coil C of strapping material. As the arm swings outwardly, under the influence of the residual curvature and resiliency of the strapping material, pin or contact member 82 will disengage switch lever or contact member 64 of the motor control switch 48 and open the switch, which will stop the rotational movement of electrical motor 16.

As soon as motor 16 is stopped, the frictional engagement of the drive wheel 20 with the outer periphery 36 of the annular tray 28 will stop additional rotation of the tray 28. In other words, the frictional drive wheel 20 will serve as a brake against dispensing tray 28 and stop any further movement thereof. Constant engagement of drive wheel 20 with periphery 36 of the tray 28 is ensured by means of compression spring 32 continuously forcing friction wheel 20 against tray 28.

If, during operation of the strapping tool, the operator moves sufficiently to deflect the outwardly extending length of strapping material C beyond its normal direction, as seen in FIG. 1, the operator can alter the payout, or normal direction of the material, simply by removing screws 56 from threaded apertures 60, placing the second set of apertures 58 in the disc 46 into alinement with the threaded aperture 60 of the spindle 3d and reinserting the screws 56. This entire adjustment of the payout direction of the strapping material C can be accomplished without removing the material from the sensor unit 50 and without altering the position of the entire dispenser assembly in its initial ground-engaging position.

Thus, it will be seen from the foregoing that the present invention provides an effective, relatively simple and efficient power-operated dispenser for strapping material which automatically senses the demand or position of the strapping material, actuates the drive means for the dispenser, satisfies the demand for the material, and continuously controls the amount of material and any slack in the material to ensure the elimination of overtravel due to rotationalinertia. No slack, or uncontrolled convolutions of material can escape from the coil and become snarled and entangled. Furthermore, the

payout direction, or normal direction of material being dispensed, can be altered without any substantial physical effort, or complete repositioning of the dispenser assembly. With selective positioning of the support arrangement for the movable sensor arm and control means, the payout direction can be simply altered by the selective alinement of apertures and bolt holes on the respective parts.

While there has been shown and described a preferred embodiment of the invention, it will be apparent that numerous variations and modifications can be made without departing from the underlying principles of the invention. there Therefore, it is desired by the following claims to include within the scope of this invention all such variations and modifications by which the results of this invention can be obtained through the use of substantially the same or equivalent means.

Iclaim:

1. A power-operated dispenser mechanism for feeding metal strapping material from a coil thereof including a rotatably mounted annular tray for supporting a coil of metal strapping material, a frame including an upwardly directed spindle secured thereto, said spindle rotatably supporting the tray, motor and drive means operatively associated with the rotatable annular tray for driving the tray in a coil unwinding direction and for feeding a length of strap material from the coil, second support means secured to the upper end of the spindle, a motor control switch and a ,pivotally mounted, movable sensor unit secured to the second support means,the movable sensor unit provided with an elongated arm having one end positioned adjacent the coil of strapping materialand providing a support and guide means for the unwound length of strap material, said elongated arm and movable sensor unit responsive to movement of the unwound length of strap material as it is supported and is guided through said elongated arm, the movable sensor unit operatively associate with the motor control switch for starting and stopping the motor in response to the movement of the sensor unit and arm toward and away from the spindle, whereby as the strap is unwound from the coil, the movable sensor unit arm will swing toward the spindle, thereby actuating the motor control switch and the motor to rotate the tray until a sufficient supply of strapping material has been dispensed therefrom and when an adequate supply of material has been dispensed the sensor unit and arm in response to the resiliency of the strap material acting on said arm will move away from the spindle to deactuate the motor control switch, thereby stopping the motor.

2. The combination set forth in claim 1 wherein said arm is a tubular member having one end positioned adjacent the innermost winding of the coil of strapping material and the opposite end positioned adjacent the motor control switch and the internal surface of the tubular arm is the strap guide and support means.

3. The combination set forth in claim l wherein the second support means is detachably secured to the upper end of said spindle means, and means for selectively positioning and securing said second support means to the spindle, whereby the support and the movable sensor unit and its arm may be positioned in various directions relative to the frame, motor, and the coil to provide adjustment of the direction of the strap material as it is unwound from the coil.

4. In a power-driven dispenser for handling resilient coil steel strapping material, the dispenser having a motor and a rotatable strapping material supporting tray, the improvement comprising a motor control and a movable arm position sensor unit for operative association with the coil strapping material to start and stop the motor in response to movement of the strapping material as it is unwound from the coil thereof, a support positioned adjacent the inner periphery of the coil of strapping material and adjacent the axis of rotation of the dis ensin tray, said motor control secured to the support, sar mova le arm plvotally mounted on the support for movement toward and away from the axis of the coil and rotatable tray and having a contact member, said motor control having a contact member carried thereby and responsive to engagement by said movable arm contact member, strap guide and supporting means forming a part of said movable arm and responsive to movement of said strapping material as it is unwound from the coil thereof, whereby as said strapping material is pulled from the coil, the movable arm will move toward the axis of the rotatable tray and by engagement of the contact members operate the motor control and start the motor to rotate the tray in a coil unwinding direction and when a sufficient supply of strap material has been fed from the coil, the movable arm will move away from the axis of the tray, disengaging the contact members and thereby deactuating the motor. 

